Snap-on adapter



FIG. 1 is a top, perspective view of a snap-on adapter showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left side elevation view thereof; and,

FIG. 7 is a right side elevation view thereof.

The broken lines and the areas inside the broken lines form no part of the claimed design. 

CLAIM The ornamental design for an snap-on adapter, as shown and described. 